The Ulster Unionist Party will field no candidates in the Foyle constituency in the Assembly elections.
It is the first time the party has failed to fight for a seat in the constituency.
UUP member Terry Wright had been selected to stand but withdrew for health reasons.
Last month Mr Wright resigned as UUP deputy chairman over the radiotherapy unit controversy at Altnagelvin hospital.
"The party is a victim of my circumstances, I had major heart surgery and my recovery hasn't been as straight forward as it should have been, " he said.
He admitted that members of the public had asked him if the row over the cancer centre had anything to do with his decision, "There's more to politics than health, I would have concerns about education in the local area and will continue to follow through with those."
Mr Wright also denied that the decision would diminish the party's presence in the Northwest.
"We've moved away from the days of wrapping someone up in a flag and saying vote for this," he said.
"The voters are likely to follow candidates they feel best represent their views.
"I would instead ask them to vote for local candidates at the council elections, voters may feel we have abandoned them but we can assure them we have not."
The UUP have never held an assembly seat in the Foyle constituency.